[plt-scheme] Student parsing problem

From: Eli Barzilay (eli at barzilay.org)
Date: Wed Jun 3 12:09:20 EDT 2009

On Jun  3, Stephen Bloch wrote:
> On Jun 3, 2009, at 11:40 AM, Eli Barzilay wrote:
> > On Jun  3, Felix Klock's PLT scheme proxy wrote:
> >> [...]
> >
> > I find it hard to justify either comments or whitespace after quotes
> > etc even in "hacker mode" -- the only reason would be to conveniently
> > comment out an expression, which is redundant when there's `#;' now.
> Eli, you're quite right for comments or whitespace immediately after  
> an INTENTIONAL quote.  But it's really easy to type a quote or a  
> backquote accidentally and not notice it because it's only a few  
> pixels, and possibly many lines away from the code you're paying  
> attention to.  As I understand it, the student problems that  
> triggered this thread were exactly such typoes.

To clarify: I *agree* with this.  I meant that I don't think that much
harm will done if no whitespace or comments are allowed after
quotations even in the usual language.

Even at the technical level, at least on a conventional keyboard it's
easy to hit a single quote instead of a semicolon and end up with:

  '; foo
  ;; bar

and the resulting typo is difficult to see.

(But these points don't apply to `#;'.)

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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